PURPOSE: To examine the time-dependent diffusion of fluorinated ((19) F) gas in human lungs for determination of surface-to-volume ratio in comparison to results from hyperpolarized (129) Xe and lung function testing in healthy volunteers and patients with chronic obstructive pulmonary disease. METHODS: Diffusion of fluorinated gas in the short-time regime was measured using multiple gradient-echo sequences with a single pair of trapezoidal gradient pulses. Pulmonary surface-to-volume ratio was calculated using a first-order approximation of the time-dependent diffusion in a study with 20 healthy volunteers and 22 patients with chronic obstructive pulmonary disease. The repeatability after 7 days as well as the correlation with hyperpolarized (129) Xe diffusion MRI and lung function testing was analyzed. RESULTS: Using (19) F diffusion MRI, the median surface-to-volume ratio is significantly decreased in chronic obstructive pulmonary disease patients (S/V = 126 cm(-1) [87-144 cm(-1) ]) compared with healthy volunteers (S/V = 164 cm(-1) [160-84 cm(-1) ], p < 0.0001). No significant difference was found between measurements within 7 days for healthy (p = 0.88, median coefficient of variation = 4.3%) and diseased subjects (p = 0.58, median coefficient of variation= 6.7%). Linear correlations were found with S/V from (129) Xe diffusion MRI (r = 0.85, p = 0.001) and the forced expiratory volume in 1 second (r = 0.68, p < 0.0001). CONCLUSION: Examination of lung microstructure using time-dependent diffusion measurement of inhaled (19) F is feasible, repeatable, and correlates with established measurements.
- Obert, A. J.
- Gutberlet, M.
- Kern, A. L.
- Kaireit, T. F.
- Glandorf, J.
- Moher Alsady, T.
- Wacker, F.
- Hohlfeld, J. M.
- Vogel-Claussen, J.
Keywords
- 19f
- diffusion
- pulmonary MRI
- surface-to-volume ratio
